Service Engine Light

What Caused My Service Engine Light To Turn On?

Research shows that nearly 30 percent of drivers in Asheville tend to ignore their service engine lights. Unfortunately, this makes them far more likely to experience an unexpected breakdown. With the use of advanced diagnostic equipment, a professional mechanic can quickly track down the source of the trouble code. Here are some common problems that will trigger a service engine light.

Loose Gas Cap

Service Engine LightYour vehicle’s onboard computer can almost instantaneously detect a loss of pressure inside the fuel tank. If your service engine light suddenly turns on after refueling, there’s a good chance you simply forgot to tighten the gas cap. Although a loose or missing gas cap may not seem serious, this issue can cause trouble in the long run.

For starters, a loose gas cap allows fumes to escape. This problem contributes to environmental pollution. Over time, you may also notice that your vehicle’s fuel economy has taken a hit. While it’s okay to drive without a gas cap for a few days, don’t make it habit.

Bad Oxygen Sensor Triggers Service Engine Light

After your vehicle surpasses the 60,000-mile mark, it’s far more likely to encounter a bad oxygen sensor. This sensor’s job is to monitor unburned oxygen coming out of your exhaust, which allows the onboard computer to properly adjusts the engine’s air-fuel ratio. When it fails, expect to see a glowing service engine light.

Most modern vehicles feature at least two oxygen sensors. The pre-cat oxygen sensor is the one that usually causes performance issues. A rough-running engine is especially common. Bad gas mileage is another problem that stems from a bad pre-cat oxygen sensor.

Bad Spark Plugs

When your vehicle is in dire need of a tune-up, its service engine light is usually activated. A mechanic must replace the spark plugs and ignition wires. This is a critical aspect of any vehicle’s factory recommended maintenance.

Bad sparks usually cause rough idling, hesitation, and hard starting. If you continue to drive your vehicle with worn-out spark plugs, things will only get worse. In some instances, your vehicle may even to even crank. The good news is that modern spark plugs have a long lifespan. Some are rated to last for more than 100,000 miles.


Engine overheating is among the most serious car problems of all. Aside from a service engine light, you’ll also likely notice stem escaping from underneath the hood. At this point, be sure to pull over as soon as possible. When an engine has started to overheat, it can self-destruct in less than a minute. From a blown head gasket to warped cylinders, several major problems may occur.

The root of the problem could be a low level of coolant, which often stems from a leaky hose or busted radiator. While adding more coolant may temporarily solve the problem, you’ll ultimately need to have the leaked professionally repaired.

Bad Catalytic Converter

Designed to help limit harmful exhaust emissions, the catalytic converter is one of the most important parts on your vehicle. When this part fails, your vehicle’s service engine light will turn on.

Oftentimes, catalytic converters fail as a result of poor maintenance. For instance, misfiring spark plugs can allow raw fuel to get into the catalytic converter. This could cause the ceramic material inside the catalytic converter to melt. Motor oil leaks can be just as damaging.

Engine Overload – Service Engine Light

Vehicles that are used for towing are more prone to experiencing engine overload. This is why it’s important to adhere to the manufacturer’s maximum tow rating. Too heavy of a load puts unnecessary stress on the engine, which could lead to big trouble. If your service engine starts to flash repeatedly, pull over and shut off the vehicle. To be on the safe side, the best approach is to call for a tow.

Car overheating

What Can Cause Engine Overheating?

Engine overheating is among the most serious car problems encountered by drivers in North Carolina. When your temperature gauge begins to approach the danger zone, it’s important to pull over as soon as possible. Not only can overheating leave you stranded, but the potential engine damage can be expensive to repair.

Car overheating

Here Are Some of the Most Common Causes of Overheating.

Leaks in the Cooling System

Leaks are by far the top reason for engine overheating. When the coolant level becomes too low, temperatures will quickly start to rise. This is why you should have your cooling system professionally inspected every year. Simply adding more coolant is only a temporary fix.

Parts prone to leaking coolant include the thermostat housing, hoses, heater core, and plastic reservoir. If a head gasket begins to leak, you have an even bigger problem on your hands. Aside from inducing engine overheating, a bad head gasket can also cause a major loss of power.

Bad Thermostat

A thermostat is a simple valve in your cooling system. However, it holds a big responsibility. The thermostat’s job is to help the engine to maintain the correct temperature.

If the thermostat fails in a closed position, the coolant will no longer be able to pass through the radiator. Engine overheating can occur quickly, especially on a hot summer day. The good news is that new thermostats are not expensive.

A Busted Hose Can Cause Overheating

It’s important for worn-out coolant hoses to be replaced in a timely manner. A burst hose will cause coolant to literally gush out of the engine. You’ll also notice steam pouring from underneath the hood.

To avoid overheating, check your coolant hoses from signs of wear and tear. Cracks and bulges in the hose are definite red flags. A soft hose also needs to be replaced.

Malfunctioning Water Pump

A properly functioning water pump barely makes a sound. If you start to hear a whining noise coming from the water pump, immediately bring in your vehicle for service. You may also notice coolant leaking from the part’s weep hole. At this point, the water pump is on borrowed time.

When a water pump fails, it can no longer propel coolant throughout the cooling system. Overheating is bound to occur at some point. The bright side is that you can expect a new water pump to last for 100,000 miles or more.

Overheating From a Bad Radiator Fan

A radiator fan, which enhances cooling by pulling air across the radiator, is an essential component. It’s designed to automatically kick on at a certain engine temperature. If the radiator fan isn’t working, overheating becomes a real possibility.

In some instances, the problem can be traced to a blown fuse. It only takes a few minutes to swap out an old fuse for a new one. You also can’t rule out a worn fan motor as the culprit. On the other hand, your fan may be in perfect working condition. A faulty temperature sensor may not be signaling the fan to turn on. Cleaning the sensor may fix the problem.

Cox Auto Service